Effect of colesevelam HCl monotherapy on lipid particles in type 2 diabetes mellitus

Lipid-Lowering Medications for Managing Dyslipidemia: A Narrative Review

Dyslipidemia refers to the change in the normal levels of one or more lipid components in the bloodstream, which include triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C). Dyslipidemia represents a substantial source of danger for cardiovascular disease (CVD). Effectively managing dyslipidemia involves a thorough strategy that includes changing one's lifestyle and using medications that are specifically designed to target the complex processes involved in lipid metabolism. Lipid-lowering treatments play a crucial role in this approach, providing a wide range of medications that are developed to specifically target different components of dyslipidemia. Statins are the main drug among these medications. Other drugs that are used with statin or as monotherapy include fibrates, omega-3 fatty acids (OM3FAs), ezetimibe, bile acid sequestrants, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, and bempedoic acid. Using the PubMed database, we reviewed the literature about dyslipidemia, drugs used for treating dyslipidemia, their efficacy parameters, and common adverse events. We also reviewed the international guidelines for treating dyslipidemia and discussed the future of lipid-lowering medications. More trials and experiments are still required to verify the effectiveness of many lipid-lowering drugs and to know their common adverse events to be able to manage them properly.

Bile acids and microbes in metabolic disease

Bile acids (BAs) serve as physiological detergents that enable the intestinal absorption and transportation of nutrients, lipids and vitamins. BAs are primarily produced by humans to catabolize cholesterol and play crucial roles in gut metabolism, microbiota habitat regulation and cell signaling. BA-activated nuclear receptors regulate the enterohepatic circulation of BAs which play a role in energy, lipid, glucose, and drug metabolism. The gut microbiota plays an essential role in the biotransformation of BAs and regulates BAs composition and metabolism. Therefore, altered gut microbial and BAs activity can affect human metabolism and thus result in the alteration of metabolic pathways and the occurrence of metabolic diseases/syndromes, such as diabetes mellitus, obesity/hypercholesterolemia, and cardiovascular diseases. BAs and their metabolites are used to treat altered gut microbiota and metabolic diseases. This review explores the increasing body of evidence that links alterations of gut microbial activity and BAs with the pathogenesis of metabolic diseases. Moreover, we summarize existing research on gut microbes and BAs in relation to intracellular pathways pertinent to metabolic disorders. Finally, we discuss how therapeutic interventions using BAs can facilitate microbiome functioning and ease metabolic diseases.

The bile acid-sequestering resin sevelamer eliminates the acute GLP-1 stimulatory effect of endogenously released bile acids in patients with type 2 diabetes

AIMS

Discovery of the specific bile acid receptors farnesoid X receptor (FXR) and Takeda G protein-coupled receptor 5 (TGR5) in enteroendocrine L cells has prompted research focusing on the impact of bile acids on glucagon-like peptide-1 (GLP-1) secretion and glucose metabolism. The aim of the present study was to assess the GLP-1 secretory and gluco-metabolic effects of endogenously released bile, with and without concomitant administration of the bile acid-sequestering resin, sevelamer, in patients with type 2 diabetes.

MATERIALS AND METHODS

We performed a randomized, placebo-controlled, double-blinded cross-over study including 15 metformin-treated patients with type 2 diabetes. During 4 experimental study days, either sevelamer 3200 mg or placebo in combination with intravenous infusion of cholecystokinin (CCK) (0.4 pmol sulfated CCK-8/kg/min) or saline was administered in randomized order. The primary endpoint was plasma GLP-1 excursions as measured by incremental area under the curve. Secondary endpoints included plasma responses of glucose, triglycerides, insulin, CCK, fibroblast growth factor-19 and 7α-hydroxy-4-cholesten-3-one (C4). In addition, gallbladder dynamics, gastric emptying, resting energy expenditure, appetite and ad libitum food intake were assessed.

RESULTS

CCK-mediated gallbladder emptying was demonstrated to elicit a significant induction of GLP-1 secretion compared to saline, whereas concomitant single-dose administration of the bile acid sequestrant sevelamer was shown to eliminate the acute bile acid-induced increase in plasma GLP-1 excursions.

CONCLUSIONS

Single-dose administration of sevelamer eliminated bile acid-mediated GLP-1 secretion in patients with type 2 diabetes, which could be explained by reduced bile acid stimulation of the basolaterally localized TGR5 on enteroendocrine L cells.

Bile acid signaling and bariatric surgery

The rapid worldwide rise in obesity rates over the past few decades imposes an urgent need to develop effective strategies for treating obesity and associated metabolic complications. Bariatric surgical procedures, such as Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG), currently provide the most effective treatment for obesity and type 2 diabetes (T2D), as well as for non-alcoholic steatohepatitis (NASH). However, the underlying mechanisms of the beneficial effects of bariatric surgery remain elusive. Recent studies have identified bile acids as potential signaling molecules involved in the beneficial effects of bariatric surgery. This review focuses on the most recent studies on the roles of bile acids and bile acid receptors Farnesoid X receptor (FXR) and G protein-coupled bile acid receptor 5 (TGR5) in bariatric surgery. We also discuss the possibility of modulating bile acid signaling as a pharmacological therapeutic approach to treating obesity and its associated metabolic complications.